Bidirectional pulse generator for video disc stylus deflector transducer
AssigneeNCR Corporation
InventorKevin C. Kelleher
Life of this patent
Estimating the term…
Abstract
A bidirectional pulse generator suitable for driving a video disc stylus deflector transducer. A differential amplifier is arranged with both its inverting and non-inverting input terminals connected for receiving a prescribed pulse waveform. First and second diodes are respectively connected between the inverting and non-inverting input terminals and a point of bilevel potential for selectively conditioning one or the other of the diodes to conduct, thereby establishing the quiescent output potential of the amplifier and concurrently shunting the pulsed waveform from one or the other of the amplifier input terminals.
Claims6
A bidirectional pulse generator for driving a video disc stylus transducer, said pulse generator energized by a supply potential and being capable of producing positive going and negative going drive pulses with respective amplitudes substantially equal to said supply potential comprising:
- respective terminals for applying first and second control signals;
- an output terminal;
- a waveform generator having an output connection, said generator being responsive to said first control signal for generating an output signal having an amplitude proportional to the duration of said control signal;
- an amplifier having a signal input terminal connected for receiving said output signal and having an output connection;
- circuit means responsive to said second control signal for selectively establishing the operating mode of the amplifier between one of an inverting and non-inverting mode and
- for selectively establishing a quiescent potential at the output connection of said amplifier at one of a relatively high and a relatively low potential, said relatively high and low potentials tending toward the relatively positive and negative potential of said supply potential;
- and
- a capacitor connected between said amplifier output connection and said output terminal.
Circuitry for energizing a video disc stylus deflector comprising:
- a waveform generator responsive to a first control signal for generating an output signal of prescribed amplitude, said generator having an output terminal;
- amplifier means having inverting and non-inverting input terminals and an output terminal;
- a first resistor connected between the waveform generator output terminal and the amplifier non-inverting input terminal;
- a second resistor connected between the amplifier non-inverting input terminal and a point of relatively low reference potential;
- third and fourth resistors having respective first ends connected to the waveform generator output terminal and the amplifier inverting input terminal respectively, and having respective second ends connected to a first node;
- a fifth resistor connected between the amplifier inverting input and output terminals, said fifth and fourth resistors determining the non-inverting gain factor of the amplifier and said fifth, fourth and third resistors establishing the inverting gain factor of the amplifier;
- a first unidirectional conduction device having a first end connected to said first node and having a second end connected to a second node;
- a second unidirectional conduction device having a first end connected to said second node and a second end connected to the amplifier non-inverting input terminal;
- means for selectively applying first and second potentials to said second node whereby one of said first and second unidirectional conduction devices is conditioned to conduct in the presence of one of said first and second potentials and the other of said first and second unidirectional conduction devices is conditioned to conduct upon application of the other of said first and second potentials;
- and
- means connecting the amplifier output terminal for energizing said stylus deflector.
Dependencies are inferred from the claim text.